Posted on 08/02/2009 11:22:56 PM PDT by neverdem
Overlooked organ harbors immune cells, serving a greater purpose than thought, new study finds
Its high time somebody said something nice about the lowly spleen. The much-maligned organ serves as a holding tank for ready-to-go immune agents called monocytes, a new study finds. These simple cells are first responders to trouble sites in the body, and the spleen is their main dispatcher, researchers report in the July 31 Science.
While its true that people can survive without a spleen, the organ is far from worthless. It recycles iron from old red blood cells, houses fresh blood cells, synthesizes antibodies and acts as a chamber in which pathogens are killed.
In the new study, scientists add to this list of duties, showing that the spleen stores monocytes in compartments close to mainstream blood vessels. This allows monocytes to travel to trauma and infection sites on short notice, says study coauthor Mikael Pittet, an immunologist at Harvard Medical School in Boston. Timing is a really important issue when you want to fight pathogens or heal after an injury, he says.
Monocytes are formed in the bone marrow and circulate in the blood stream. When the immune system detects an infection or trauma, immune proteins usher monocytes to trouble sites. There, a first wave of inflammatory monocytes engulfs pathogens, takes apart dead cells and cleans up debris from the battle. After a few days, a second wave, this time of anti-inflammatory monocytes, arrives to foster the rebuilding process.
Pittet teamed with Harvard colleagues Filip Swirski, Matthias Nahrendorf and others to ascertain these monocytes origins.
In a series of experiments in which they induced heart attacks in mice, the researchers showed that many monocytes arriving at traumatized heart tissue could be traced back to the spleen.
Further tests showed that the compound angiotensin-II, which...
(Excerpt) Read more at sciencenews.org ...
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FReepmail me if you want on or off my health and science ping list.
Now they tell me.
I just had it removed to lose weight.
I was going to ping you.
Oh nevermind. LOL
It’s like the police station in your body... jail cells and all! That’s cool. :)
I sure hope so 'cause I ain't got one.
I will never tell another Spleen Joke in my life.
.......I will never tell another Spleen Joke in my life.....
Strangely believe it I found such a thing....
Daughter: Taylors uncle found out that he had more than one spleen.
Mom: Well, then he has some ex-spleening to do.
Oh great, we've had to worry about being drugged in Vegas and having our kidneys stolen while in our own hotel rooms now they're going to be coming after our spleens too.........
Not exactly new news - people have known this for something like 30 years. Sheeesh.
Great article though. I wonder if monocytes can be introduced artificially to heart attach patients?
insert spleen as a generic organ when talking about health related matters. Just add and it promotes healthy spleen function to any sentence about nutrition and wait for the laughs.I bet Drs have a load of them too.
Back in October of 1962 my brother was hurt while playing football. He had some internal bleeding. The doctors operated on him and during the surgery, his spleen was removed. I do not remember if his spleen had been damaged. However, I do remember my father telling me that the doctor said that the spleen was non essential.
In August of 1963, my brother was working at a summer camp and contracted spinal meningitis. He was the only person at the camp that did. He was dead within 48 hours and the doctors were unsure why that happened.
About ten years later we learned that he very well may have lived if he had his spleen
A current paradigm states that monocytes circulate freely and patrol blood vessels but differentiate irreversibly into dendritic cells (DCs) or macrophages upon tissue entry. Here we show that bona fide undifferentiated monocytes reside in the spleen and outnumber their equivalents in circulation.
This is a study published last month, not 30 years ago.
I could publish an article tomorrow proving that the earth was round, but that wouldn’t make it new. Point is that clinicians have known about the downside of splenectomy for many, many years. Look it up.
I'm not disputing that the downside of splenectomy has been known for decades. The point is that monos are predominantly stored in the spleen, not the general circulation.
Very true. Turns out splenectomy patients have particular difficulties with so called “encapsulated bacteria” which generally means pneumococcus, hemophilus, and N. Meningitis. The last of these is the frequent cause of fatal meningitis, although it’s possible for all three to do it.
Ways to save damaged spleens just didn’t exist in 1962 - that came much later like the 80’s or so. And even there, they don’t always work - sometimes the spleen just has to come out despite all best efforts to maintain it. I think the comfort to be found, if any, is that he got state of the art care for his time, things just hadn’t evolved where they needed to be in 1962.
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